If anyone is interested, Dark Matter is actually a.. "substance" that doesn't really exist... or kind of does maybe.

Dark Matter is actually a theory. It's a type of "energy" that holds galaxies together, rather than having them spinning off, as the gravitational pull of each planet/stars/etc aren't enough to keep galaxies together. They do theoretic tests that show how the galaxies should expand and retract, with their relative mass. And... they don't retract. They have to add in a source of "energy" that defies typical physics, and doing so makes the tests stable and play out like they should.

At least, that is what I had learned about it, a couple years ago. My memory might have been warped from what it was, or the theory may have changed, since then.

WELLLL what you are thinking of is dark energy. dark matter however has actual effects that are seen. its gravitational lensing , or the gravity of an invisible object bending light, yet we see nothing.

tl:dr; dark matter and matter ate each other up and dueled it out at the beginning of time and matter one out, but now we have ridiculous amounts of nothingness in between. Dark matter now is very scarce.

This is actually pretty accurate, but what you're describing is actually what's known as dark energy. Dark matter is a similar theory that states that there are certain parts of far-off galaxies where stars cluster closer together than they should be given their mass. Their collective gravity shouldn't be strong enough to hold the system as close together as it is.

Essentially, scientists have reasoned that the only way for it to make sense within the bounds of physics is for there to be excessively large amounts of matter floating around in space that doesn't produce light and we haven't learned how to "see" or detect yet. The phenomenon is observed commonly enough that on the spectrum of space theories, it's far closer to black holes than it is to worm holes.

First: The universe isn't accelerating, it's slowing down. Which signifies that the "Big Bang" is a repeated cycle that happens every... bajillion years. It will eventually stop expanding, begin to retract, and eventually compact, and eventually cause another "Big Bang".

Second: Galaxies without dark energy will have it's planets and stars and stuff fly everywhere in very unexpected ways. If gravity was the only thing holding a galaxy together, the gravity of each planet and star would pull each of them in different ways, causing the chaotic positioning.

Something about the Dark Energy (either it's unknown, or it's just unknown to me), keeps the pieces of the galaxy from spreading out in such chaos. And instead, in sync with the gravitational pull, causes the pieces to fall into place more evenly. Spiral galaxies are a prime example of this, as without the Dark Energy, it would just be a *********** of stars, planets, and such, just crashing into each other, and expanding away from the focal point.

Well, I was right. But I was told that I was wrong. So I started speaking what I was told was right, when it was really wrong.

Long story short, I was right about Dark Matter holding the galaxies together, I took someone's word saying it was actually Dark Energy, and without checking evidence, started to say it was in fact Dark Energy. Thus I feel slightly idiotic, and a bit gullible for that.

I thought you were assuming that dark matter and dark energy were the same because of how you used matter and energy in the same way.

If I'm not mistaken, and someone correct me if I am, I believe it is
-dark matter that creates gravitational forces larger than expected (ie. Galaxies being held together)
-dark energy that causes the universe to expand at a more rapid rate over time instead of slowing down

Sorry for the blunt response, I'm also tired and didn't feel like remembering everything I know about them so I left it at that. You should look into this and other science related.. things.. It's all interesting.

Even Bio. Chemistry I only like the basics, and physics is prolly more work than it's worth to solve.

But space and earth sciences are extremely interesting. I made some posts a long ass time ago about history repeating itself over and over again. If i wasn't lazy, I'd dig it all up. If I wasn't doubly lazy, I'd just type it all back out.

Biology is also really easy to follow, compared to the other sciences. That's what makes it so "fun" for me. It's just simple and easy, and easy to remember (for the most part). At the same time, when you get far, far into it, it is extremely complex... I wonder...